This invention relates to brake and clutch assemblies and, more specifically, to piston operated brake and clutch assemblies wherein the clutch and brake are alternately engaged. The most pertinent prior art known to the applicant includes U.S. Pat. Nos. 3,177,994 to Jewson; 3,262,525 to Ehlke et al; and 3,696,898 to Sommer.
Various types of hydraulic clutch and brake mechanisms have long been employed where intermittent drive and braking is required for satisfactory operation. For example, such combination clutch and brake mechanisms are frequently employed in saw mills, in connection with rock crushers, and other similar applications.
Perhaps a more prominent field of use of such mechanisms has been their use as combination steering clutch and brake assemblies for controlling the locomotion and direction of crawler-type tractors.
Heretofore, difficulty has been encountered in attempting to design a satisfactory clutch and brake unit. Typical problems encountered are providing such a mechanism that is easily manufactured and subsequently serviced. One frequent cause for service is the failure of actuating pistons and seals since many such units employ pistons which experience both axial and rotary movement within the bores in which they travel.
A further problem of substantial moment has been providing such a mechanism that is axially compact, that is, of minimum size from its input shaft to its output shaft.